1. Field of the Invention
This invention pertains to composite air and electrical couplings designed for use particularly in the operation of truck-trailer units.
2. Description of the Prior Art
U.S. Pat. No. 3,523,266 illustrates a composite air and electrical coupling in which a single air line of the vehicle can be coupled to the air line of the trailer. More recent tractor-trailer rigs, however, have required two pneumatic connections. The recent tractor-trailer rigs have a pneumatic reservoir for providing power or actuating air to the brakes on the trailer and a control air valve which can be controlled from the vehicle cab to allow air to flow from the reservoir to the brakes and to vent the brakes when the brakes are deenergized. The details of these tractor-trailer air-actuated units are conventional and will not be further described. Suitable systems are manufactured by Bendix-Westinghouse Automotive Air Brake Company of Alyria, Ohio, U.S.A.